diff --git a/swift/proxy/server.py b/swift/proxy/server.py
index 2cb329e064..99b7201ab4 100644
--- a/swift/proxy/server.py
+++ b/swift/proxy/server.py
@@ -645,7 +645,7 @@ class Controller(object):
                         raise
                 res.app_iter = file_iter()
                 update_headers(res, source.getheaders())
-                update_headers(res, {'accept-ranges':'bytes'})
+                update_headers(res, {'accept-ranges': 'bytes'})
                 res.status = source.status
                 res.content_length = source.getheader('Content-Length')
                 if source.getheader('Content-Type'):
@@ -655,7 +655,7 @@ class Controller(object):
             elif 200 <= source.status <= 399:
                 res = status_map[source.status](request=req)
                 update_headers(res, source.getheaders())
-                update_headers(res, {'accept-ranges':'bytes'})
+                update_headers(res, {'accept-ranges': 'bytes'})
                 if req.method == 'HEAD':
                     res.content_length = source.getheader('Content-Length')
                     if source.getheader('Content-Type'):